I say use it; if it's incorrect, someone will be more than happy to let you know.
I like this one:
Ad astra per alia porci (To the stars on the wings of a pig).
According to WIKI, this was a favorite saying of John Steinbeck because a professor told him that he would be an author when pigs flew.
Every book he wrote is imprinted with this insignia.
Take that, professor-know-it-all!
Syl